Aluminium overload and response to recombinant human erythropoietin in patients under chronic haemodialysis.

In this work, of 51 patients treated by rHuEpo, 25 were selected for study. The selection criteria were absence of clinically evident causes of anaemia other than end-stage renal failure, such as chronic infection, active systemic disease, bleeding sites, and vitamin B12 or iron deficiencies. Serum aluminum was assessed before dialysis and the presence of aluminium overload was confirmed by a DFO test. rHuEpo was given in a dose of 50 U/kg body-weight after each dialysis session three times weekly and the response to treatment was evaluated monthly for 8 months. Our data showed significant correlation between serum aluminum and the response to rHuEpo. The response was significantly greater in those with lower serum aluminium. We conclude that the aluminium load in chronic haemodialysis patients may have an effect on the response to rHuEpo.     

Lipid profile in haemodialysis patients treated with recombinant human erythropoietin

Background: The long-term effect of recombinant human erythropoietin (rhEPO) on the blood-lipid profile has not been well documented. The aim of this study was to evaluate whether rhEPO therapy affects the lipid pattern. Methods: A group of 102 maintenance haemodialysis patients were treated for 2 years with rhEPO given intravenously at the end of the dialysis session. Attempts were made to keep the haemoglobin (Hb) at 10-11 g/dl and/or the haematocrit (Hct) at 30-35%. Twenty maintenance haemodialysis patients not treated with rhEPO were examined as controls. Total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, apolipoproteins A1 and B, and lipoprotein (a) [Lp (a)] were assessed at baseline (without rhEPO), and 1 and 2 years after the beginning of treatment. Hb, Hct and ferritin were measured monthly, and Kt/v was evaluated monthly and kept above 1.1. Results: During follow-up, in both groups, there was a significant increase in Apo A1 and no significant changes in the other lipid parameters. In the treated group, Hb and Hct increased significantly after the fourth month of treatment. Conclusions: Erythropoietin therapy does not affect significantly the levels of total cholesterol, LDL- and HDL-cholesterol, triglycerides, Apo B and Lp (a) in maintenance hemodialysis patients.     

Plasma endothelin in haemodialysis patients treated with recombinant human erythropoietin

Predialysis plasma endothelin (ET) values were followed duringthe first 8 weeks of rHuEpo treatment in 12 patients on routinehaemodialysis. Mean plasma ET was significantly increased inuraemic patients before rHuEpo (27.911.4 pmol/1), as comparedto 40 healthy controls (16.55.7 pmol/1) (p<0.0001). UnderrHuEpo treatment, predialysis values remained unchanged althoughdiastolic blood pressure increased after 2 and 6 weeks. We foundno correlation between ET and haemoglobin or blood pressurebefore or under rHuEpo treatment. These results confirmed thehigh levels of plasma ET in haemodialysis patients, but no increasewas observed during rHuEpo treatment.     

Haemodynamic effect of recombinant human erythropoietin on hypotensive haemodialysis patients

The haemodynamic effects of recombinant human erythropoietin (rHuEpo) on anaemic haemodialysis patients suffering from chronic hypotension were examined. rHuEpo increased the haematocrit to around 30% and increased diastolic blood pressure by 12.4%, statistically significant. Correspondingly, the total peripheral resistance index increased 42.3% while the cardiac index decreased 24.4% (P less than 0.05) respectively. Blood volume, plasma renin activity and plasma noradrenaline did not change significantly. The extent of blood pressure elevation and haemodynamic alteration did not differ from our previous report on anaemic haemodialysis patients without hypotension. The incidence of hypotensive episodes and fluid supplementation did not change significantly after rHuEpo treatment. In conclusion, by using rHuEpo, approximately a 10% increase of blood pressure can be expected. However no substantial improvement in hypotensive episodes can be expected in chronic haemodialysis patients suffering from hypotension.     

Low-dose aspirin does not prevent thrombovascular accidents in low-risk haemodialysis patients during treatment with recombinant human erythropoietin

Treatment of the anaemia of renal disease with recombinant humanerythropoietin results in an improvement of haemostasis andan increased risk of thrombovascular accidents. In this prospective,placebo-controlled, double-blind, and cross-over study, theeffects of low-dose acetylsalicylic acid (30 mg daily) on thromboticand bleeding events during the initial period of treatment witherythropoietin in anaemic haemodialysis patients without previousthrombovascular accidents or known increased risk for thrombosiswere investigated. During correction of the haematocrit andthe first 3 months thereafter, group A (n = 68) received placeboand group B (n = 69) 30 mg acetylsalicylic acid daily. Cross-overtook place after the 3rd month of a stable haematocrit. Thestudy ended 3 months later. Target haematocrit (30–35%) was reached in 12.4±8 weeks (M ± SD). In group A the bleeding time was 382±285s, decreasing to 282±208 before cross-over (P<0.0l),and increasing to 395±271 (P<0.05) there after. Ingroup B the bleeding time was 390±381 s, 406±267(NS), and 285±238 (P<0.05) respectively. Twenty-twothrombovascular accidents were seen (16%, 13 during acetylsalicylicacid and 9 during placebo, NS), including 17 fistula thromboses.The incidence of bleeding events was not significantly differentbetween regimens. In conclusion, erythropoietin treatment resulted in a reductionof the bleeding time. When 30 mg acetylsalicylic acid was takenduring the treatment, the bleeding time did not decrease. Theregimen did not result in an increased number of bleeding events,but neither were thrombovascular accidents prevented in low-riskpatients.     

Exercise in hemodialysis patients after treatment with recombinant human erythropoietin

To assess the effect of substantial increases in blood hemoglobin (Hb) caused by treatment with recombinant human erythropoietin (rhEPO) on exercise capacity in maintenance hemodialysis patients, we evaluated 10 patients (7 men and 3 women) at a mean age of 44.3 +/- 8.4 years on maintenance hemodialysis for a mean of 29.7 +/- 30.2 months by treadmill exercise to exhaustion. The patients were tested before administration of rhEPO and after a minimum 1 g/dl rise in Hb. With a change in Hb from 7.1 +/- 1.4 to 9.8 +/- 2.1 g/dl, peak oxygen consumption (VO2 peak) with exercise increased 50.3 +/- 9% (T1 = 15.1 +/- 5.3, T2 = 22.7 +/- 4.6 ml O2/kg/min, p less than 0.05). Respiratory exchange ratio (RER) at a given submaximal exercise level (3 mph, 6% of elevation) decreased significantly (T1 = 1.13 +/- 0.24, T2 = 0.92 +/- 0.08, p less than 0.05). The rhEPO-mediated increase in Hb was associated with an increased VO2 peak--an improvement of the peak exercise capacity and a reduced submaximal RER--reflecting a reduction in anaerobic metabolism at activities of daily living.     

The benefits of treatment with recombinant human erythropoietin in cancer patients

IMPROVED QUALITY OF LIFE WITH EPOETIN BETA: In a study against a placebo, there was evidence that the quality of life scores were significantly improved in patients treated with epoetin beta, whether they exhibited a solid tumour or a malignant lymphoma. The same was noted in children with cancer exhibiting severe neoplasia and treated with chemotherapy. The efficacy and tolerance to treatment were equivalent, whatever the administration regimen. IN PATIENTS SUFFERING FROM MYELODYSPLASTIC SYNDROMES: A particular entity among malignant blood diseases, myelodysplastic syndromes are at the origin of anaemia against which repeated transfusions and growth factors are proposed with varying results and disadvantages, and against which erythropoietin may be moderately effective (a mean of 25% in non-selected cohorts of patients). DEPENDING ON THE PROTOCOLS OF ERYTHROPOIETIN ADMINISTRATION IN CASES OF MYELODYSPLASTIC SYNDROMES: Recombinant human erythropoietin, irrespective of its concentration in myelodysplastic cell culture, does not appear capable of restoring normal erythropoiesis. The influence of prolonged treatment is not admitted by all. The effects of the addition of growth factors (notably G-CSF) are obvious but some are controversial because of the costs and the prolonged duration of such treatments.     

Hemodynamic changes in hemodialyzed patients during treatment with recombinant human erythropoietin

Evolution of cardiac index in 12 patients with severe renal anemia on regular hemodialysis (hematocrit 19.9 +/- 2.8%) was studied during the first 4 months of treatment with recombinant human erythropoietin (rhEPO). At the end of the study period, hematocrit rose to 31.1 +/- 3.5% (p less than 0.001) and cardiac index significantly decreased (5.34 +/- 1.25 vs. 3.81 +/- 0.84 liters/min/m2, p less than 0.001). Cardiac index fell mainly because of reduction of stroke volume (108 +/- 27 vs. 81 +/- 25 ml, p less than 0.001), while heart rate did not change during the study period. Before starting rhEPO cardiac index was elevated in 11 out of the 12 patients, whereas after 4 months of treatment this was only maintained in 4 of them. We conclude that substitution with rhEPO in hemodialysis patients significantly decreases cardiac index, confirming anemia as the main factor for hyperdynamic circulatory state in these patients. Whether this reduction in cardiac index will ameliorate cardiac morbidity or not and hematocrit levels for achieving the major benefits require further studies.     

Long-term therapy with recombinant human erythropoietin increases CD8+ T-cell apoptosis in haemodialysis patients.

BACKGROUND: We intended to assess the intensity of apoptosis in the CD4+ and CD8+ T-lymphocytes of haemodialysis (HD) patients on recombinant human erythropoietin (rHuEpo). METHODS: The expression of Fas, tumour necrosis factor-alpha receptors (TNFRI and TNFRII) and the CD28 molecule on lymphocytes was evaluated in 15 HD patients before and during treatment with rHuEpo. In cultures of peripheral blood mononuclear cells (PBMCs) stimulated with rHuEpo, phytohaemagglutinin and camptothecin, our measures of apoptosis were the percentages of cells with subdiploid DNA content and of annexin V-stained cells. Results, Therapy with rHuEpo did not affect CD4+ T cells but decreased the percentage of CD8+ T cells in peripheral blood. The intensity of apoptosis in both CD4+ and CD8+ T cells at baseline was lower in HD patients than in healthy volunteers, and increased in those treated with rHuEpo. In vitro, rHuEpo did not induce apoptosis in PBMCs. The percentage of CD8+Fas+ T cells was constant, while that of CD8+TNFRI+ cells declined during follow-up. There was an increase in the percentage of CD28+ T cells, mainly in the CD8+ compartment, as early as 1 month after the introduction of rHuEpo. CONCLUSIONS: Treatment with rHupo caused a decline of CD8+ T cells in HD patients, which most probably was mediated via the TNFRI-related apoptotic pathway and was independent of Fas expression. Apoptosis in vitro was not directly influenced by rHuEpo, suggesting that the process in vivo was only initiated by rHuEpo supplementation.     

Dialysate related cytokine induction and response to recombinant human erythropoietin in haemodialysis patients.

BACKGROUND: Chronic inflammatory disorders or infections represent a major cause of hyporesponsiveness to recombinant human erythropoietin (rHuEpo). To test the hypothesis that dialysate-related cytokine induction alters the response to rHuEpo, we conducted a prospective study with matched pairs of chronic haemodialysis patients. We compared the effect of two dialysis fluids, differing in their microbiological quality, on the rHuEpo therapy. METHODS: Thirty male patients with end-stage renal disease maintained on regular haemodialysis were assigned either to a group treated with conventional (potentially microbiologically contaminated) dialysate (group I) or to a group treated with online-produced ultrapure dialysate (group II). Randomization was stratified according to the maintenance dose of rHuEpo necessary to maintain a target haemoglobin level of 10-10.5 g/dl. Patients were followed for 12 months. Kt/V was calculated by the formula of Daugirdas. Haemoglobin levels were measured weekly and serum ferritin concentrations were determined at 6-week intervals. C-reactive protein (CRP) and interleukin-6 (IL-6) was measured by an ELISA at the start of the study and after 3, 6 and 12 months. RESULTS: In group I, continuous use of bicarbonate dialysate did not change the rHuEpo dosage given to achieve the target haemoglobin level and was associated with elevated surrogate markers (CRP, IL-6) of cytokine-induced inflammation. The switch from conventional to online-produced ultrapure dialysate in group II resulted in a lower bacterial contamination with a significant decrease of CRP and IL-6 blood levels. It was accompanied by a significant and sustained reduction of the rHuEpo dosage, which was required to correct the anaemia. Using multiple regression analysis, IL-6 levels are shown to have a strong predictive value for rHuEpo dosage in both groups. CONCLUSIONS: Our data demonstrate that dialysate-related factors such as low bacterial contamination can induce the activation of monocytes, resulting in elevated serum levels of IL-6. Dialysate-related cytokine induction might diminish erythropoiesis. The use of pyrogen free ultrapure dialysate resulted in a better response to rHuEpo. Not only would it save money, but it would also help to maintain an optimal haemoglobin level without further increase in rHuEpo dosage.     

The treatment of renal anaemia in CAPD patients with recombinant human erythropoietin

Fifteen severely anaemic patients receiving CAPD were treated with subcutaneous recombinant human erythropoietin (Epo). Ten subjects had a good response with the haemoglobin concentration increasing from less than 8 g/dl to greater than 10 g/dl within 16 weeks. Four patients had a poor response, which was due to infection in two, myelofibrosis in one and unknown cause in another. Epo was ineffective in the remaining individual, probably due to the presence of occult metastatic carcinoma. Iron supplementation in the form of intravenous iron dextran was given to 12 patients when transferrin saturation decreased below 20%. There was a significant increase in red cell volume (P less than 0.005), with a decrease in plasma volume (P less than 0.005). Red cell iron turnover increased (P less than 0.05) but there was no change in red cell lifespan or deformability. Biochemical parameters remained unaltered, as did peritoneal function. Exercise duration improved (P less than 0.001), as did maximal oxygen consumption (P less than 0.01). Four patients required an increased dose of hypotensive drugs. Epo is a safe effective therapy for the anaemia of CAPD subjects.     

Intravenous versus subcutaneous administration of recombinant human erythropoietin in patients on haemodialysis and CAPD.

The most effective route of administration of rHuEpo is still a matter of discussion. Prospectively we studied subcutaneous (s.c.) versus intravenous (i.v.) administration in three comparable groups of patients; HD-s.c. (n = 9), HD-i.v. (n = 11), and CAPD-s.c. (n = 9). All the groups initially received 50 units/kg three times weekly. During the first 8 weeks dose adjustments were made only if target haemoglobin exceeded 11.3 g/dl (7 mM). Target haemoglobin was reached after 84 (42-98) days in the i.v. group and 42 (14-77) and 42 (28-56) respectively in the HD-s.c. and CAPD groups. The difference was statistically significant (P less than 0.05). Even the cumulative doses to reach target haemoglobin were significantly less in the two s.c. groups. To maintain haemoglobin at about 11.3 g/dl, weekly doses were as follows: HD-i.v. 125 U/kg (86-168), HD-s.c. 63 U/kg (20-85), and CAPD 72 U/kg (31-100). The total observation time after the target haemoglobin level was reached, was median 130 (114-264) days. The difference between the i.v. group and the two s.c. groups was statistically significant, (P less than 0.05) whereas there was no difference between the s.c. groups. We conclude that s.c. administration of rHuEpo is more effective in induction as well as in maintenance therapy and that s.c. administration is equally efficient in HD and CAPD patients.     

Once weekly versus twice weekly subcutaneous administration of recombinant human erythropoietin in haemodialysis patients.

Optimal route and frequency of administration of recombinant human erythropoietin (rHuEPO) have not yet been determined. There is some evidence to suggest that subcutaneous administration of rHuEPO may be more effective than the intravenous route in reversing renal anemia. It is also unclear whether rHuEPO is more effective when given by a large intermittent dose or by more frequent multiple divided doses. We have compared the effect of twice weekly versus once weekly subcutaneous administration of rHuEPO in two groups of haemodialysis patients. At the end of 12 weeks of treatment with rHuEPO, the mean haemoglobin levels had risen from 6.9 +/- (SD) 0.7 to 8.9 +/- 1.3 g/dl in the once weekly group and from 7.2 +/- 1.0 to 9.3 +/- 1.6 g/dl in the twice weekly group. The average doses of rHuEPO used during the study were 127 +/- 6 and 115 +/- 18 U/kg body weight/week for the once weekly and twice weekly groups, respectively. Subcutaneous administration of low-dose rHuEPO is effective in reversing renal anaemia. Similar responses were obtained with once weekly and twice weekly regimens.     

Aluminium content of water for injection used with recombinant human erythropoietin.

Human recombinant erythropoietin is of proven value in the treatment of the anaemia of renal failure. The aluminium content of 36 ampoules of water for injection supplied for use with recombinant erythropoietin has been measured and ranged from 24 to 450 micrograms/l, with a median of 251 micrograms/l. In three samples, which may have been contaminated on opening, the range was from 1770 to 6160 micrograms/l. In Water for Injection BP, values ranged from 66 to 140 micrograms/l with a median of 99 micrograms/l. Reconstituted erythropoietin did not contain any more aluminium than could be accounted for by the water. Ampoules of a second brand of erythropoietin, supplied already in solution, contained from 506 to 837 micrograms/l aluminium (median 682 micrograms/l). In view of the lifelong duration of erythropoietin therapy clinicians and pharmaceutical companies should be aware of this potential problem. Although the amount of aluminium delivered with each injection is usually less than 4 micrograms, it is suggested that active steps are taken to establish a British Pharmacopoeia limit on the aluminium content of injections.     

The basis of treatment with recombinant human erythropoietin

EXPERIMENTAL DATA: A line of transgenic mice overexpressing erythropoietin was created. These mice retained their capacity to reduce their gastro-intestinal absorption of iron and to regulate the changes in their iron metabolism and they could serve as a model for the in vivo study of iron homeostasis and erythropoiesis. NEW INDICATIONS FOR RECOMBINANT HUMAN ERYTHROPOIETIN: After chronic terminal kidney failure, the treatment of chronic dialysed kidney failure patients and patients treated with azathioprine or patients having undergone surgery and requiring transfusion, other indications have been proposed. Such as anaemia in children following inadequate production of endogenous erythropoietin and/or direct inhibition of the erythroid cell line in the bone marrow or anaemia during pregnancy and, since the Sixties, anaemia during cancer. TO ASSESS THE PHYSIOPATHOLOGY OF ANEMIA:In anaemic patients suffering from a malignant blood disease, it would be useful to calculate the relationship between the predicted and observed rates of erythropoietin as well as the transferin serum receptors.     

A study of recombinant human erythropoietin in the treatment of anaemia of chronic renal failure in children on haemodialysis

This was an open-label multicentre study of recombinant human erythropoietin (r-HuEPO) in 116 children aged 6 months to 20 years with anaemia of chronic renal failure undergoing haemodialysis. Haemoglobin concentration at entry ranged from 3.4 to 9.5 g/dl. r-HuEPO was given intravenously two or three times per week, the starting dose being 75 U/kg per week. This was subsequently titrated in steps of 75 U/kg per week with the goal of increasing haemoglobin concentration at the rate of 1 g/dl per 4 weeks into the range 9.6–11.2 g/dl (6–7 mmol/l), with treatment then continued for up to 1 year with the aim of maintaining the haemoglobin concentration within the target range. Of the 115 children in whom efficacy could be evaluated, 93 (81%) achieved the target haemoglobin and a further 6 had a rise in haemoglobin concentration of at least 2 g/dl. At 52 weeks, the median maintenance dose for children<30 kg was 225 U/kg per week, compared with 107 U/kg per week for children 30 kg. Analysis suggested that 150 U/kg per week would have been a more appropriate starting dose. The mean transfusion requirement fell from 8.9 to 0.7 units/patient per year. Of the 22 patients who failed to reach the target, 15 went on to transplantation and left the study prematurely. Sub-group analysis showed that similar doses lead to similar rates of rise in haemoglobin regardless of the severity of the original anaemia. Assessment of quality of life suggested that this may have improved with r-HuEPO. Twenty-four children needed initiation or increase of anti-hypertensive medication, suggesting that successful r-HuEPO therapy was associated with a tendency towards increased blood pressure. However, there were no significant mean changes in blood pressure, suggesting that the problem was successfully addressed by the changes in treatment. No child developed anti-r-HuEPO antibodies. The overall safety profile was excellent and no new r-HuEPO toxicities were identified in children.     

Long-term therapy with recombinant human erythropoietin decreases percentage of CD152(+) lymphocytes in primary glomerulonephritis haemodialysis patients.

BACKGROUND: Recombinant human erythropoietin (rHuEpo) may affect the human immune system. The aim of the study was to examine changes in CD4(+) and CD8(+) T-cell subpopulations, the expression of the inhibitory molecule, CD152 on T lymphocytes and the levels of interleukins (IL) 2, 6, 10, 12 and tumour necrosis factor alpha (TNF alpha) in primary glomerulonephritis chronic haemodialysis (HD) patients before and under rHuEpo treatment. METHODS: Expression of T-cell surface molecules was measured in 14 HD patients ex vivo by flow cytometry of lymphocytes sampled from peripheral blood and in vitro using whole blood cell cultures stimulated either with phytohaemagglutinin (PHA) or with physiological as well as non-physiological doses of rHuEpo. The concentrations of the cytokines were measured in the supernatants from non- or PHA-stimulated cultures using bioassays (IL2, IL6, TNF alpha) or ELISA tests (IL10, IL12). RESULTS: Compared with findings before the start of rHuEpo therapy the CD4(+)/CD8(+) ratio increased after 1 year of follow-up, whereas the percentage of CD152(+) peripheral blood lymphocytes decreased. The increase of the CD4(+)/CD8(+) ratio was dependent on a decrease of the percentage of CD8(+) cells. The decrease of CD152(+) population affected mainly CD8(+)CD152(+) cells. All these effects became apparent after 6 months of rHuEpo treatment. In vitro stimulation of whole blood cultures revealed that the addition of PHA up-regulated the percentage of CD152(+) lymphocytes, while physiological concentrations of rHuEpo decreased the percentage of CD8(+)152(+) T cells. None of the stimuli used affected the percentage of CD8(+) T cells. The pattern of the cytokines shifted toward TH1 phenotype (increase of IL2 and 12 levels) with a decreased level of proinflammatory cytokines (decrease of IL6 and TNFalpha levels). CONCLUSIONS: The observed decrease of CD152(+) lymphocytes together with the decrease of CD8(+) cells may reflect the improved immune response observed in HD patients under rHuEpo treatment.